


Late-Night Cutting

by Wingless_Hummingbird



Category: Undertale (Video Game)
Genre: Bad Sanses | Nightmare's Gang (Undertale), God Complex, Hurt/Comfort, M/M, Manipulation, Mental Health Issues, Psychological Trauma, Self-Harm, Some Fluff, Twisted Romance
Language: English
Status: Completed
Published: 2021-02-04
Updated: 2021-02-04
Packaged: 2021-03-16 02:40:53
Rating: Mature
Warnings: Creator Chose Not To Use Archive Warnings
Chapters: 1
Words: 1,341
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/29199999
Author URL: https://archiveofourown.org/users/Wingless_Hummingbird/pseuds/Wingless_Hummingbird
Summary: Nightmare drums his fingers on the armrest of his throne. It’s early afternoon and Killer hasn’t gotten out of bed. The god of negativity knows exactly it’s one of those days...But when Killer just doesn’t show up, uncertainty grows and Nightmare finally knocks on Killer’s door...It's time to educate his puppet on how Nightmare really feels about the other's carelessness.
Relationships: Sans/Sans (Undertale)
Kudos: 44





	Late-Night Cutting

**Author's Note:**

> I just love Nightmare x Killer stories! So, I decided to write one myself...
> 
> WARNING: This is NOT how to deal with somebody who self-harms... This is quite morbid, don't try this at home. ^^

Nightmare drums his fingers on the armrest of his throne. It’s early afternoon and Killer hasn’t gotten out of bed. The god of negativity knows exactly it’s one of those days.

Each member of his team struggles with the aftermath of terrifying events in their universes. Nightmare is used to it. On some days, some members are simply unavailable due to another breakdown. He’s not mad about that, quite the contrary, honestly. Those days make them vulnerable and susceptive to his manipulation.

The negative emotions on days like these are like coffee for his body. Especially since things got softer in his castle over time. And he’s not talking about the perfectly soft sandwiches he receives for breakfast every single day. Horror enjoys preparing food a bit too much.

He leaves Killer alone for the whole day. But when his right hand doesn’t appear the next day either, uncertainty grows. Checking on his most loyal member won’t hurt. Just in case there was more going on than usual.

At 10pm, Nightmare finally knocks on Killer’s door. No answer. Too bad for the other skeleton that a god doesn’t need permission to enter. A tentacle opens the door slowly, giving Killer enough time to prepare for his entry.

A wave of negativity washes over him and he shivers delighted. All lights are switched off, but Killer’s red soul can easily be spotted through the darkness. The glowing object isn’t as perfectly round as it normally is and judging by its position, the skeleton is sitting on his bed.

What irritates Nightmare the most is the silence that greets him. He flicks the lights back on.

As expected, Killer sits on his bed and sharpens one of his knives absently. A bunch of different sized knives sit neatly on the bed beside him. The faint smell of marrow and dust licks at Nightmare’s consciousness.

He has done it again. Killer doesn’t look up but stops his movement.

Night swallows his pride, calmly walks towards his puppet, and sits down on a spot that isn’t covered with knives or dried marrow. Fresh cuts all over Killer’s shirtless body serve as silent witnesses to the horror that happened inside of this room. Most cuts are flawlessly parallel but differ in depths.

“That’ll take a while to heal.”, Nightmare comments nonchalantly. It’s not uncommon for the traumatized skeleton to harm himself from time to time. Night doesn’t really understand the need to do that, but he theoretically gets the idea. He prefers inflicting pain than receiving it, for he experienced enough pain back in Dreamtale.

“Did it feel good at least?”, he pushes him to say something. But Killer remains completely unresponsive.

His tentacles twitch and he exhales audibly. But in this state, the god of negativity is willing to forgive Killer this inappropriate behavior towards him, his boss and savior. “…Seems like you will be unable to work for the next three days.”, Nightmare knows exactly which buttons he needs to push to get an answer.

And that’s the moment when Killer jolts. “What?! Why? I can still fight. I’m just… heh… a little low on HP.”, Killer starts confidently, but his statement ends with nothing more than a whisper.

Nightmare rolls his eyelight, sending the injured skeleton on a mission would be close to a death sentence. “Killer, I tolerate your coping mechanism, but I certainly will not tolerate you getting yourself in danger.”, the way he speaks leaves no room for discussion.

Killer sighs defeated, liquid hate drips out of his eye sockets as he lowers his head. The variety of negative emotions presented to Nightmare are intoxicating.

The gooey skeleton smirks mercilessly, stands back up and takes one of the recently sharpened knives. It highly displeases Killer every time somebody takes one of his knives. But he doesn’t protest. Nightmare is his boss, his master, his god. He doesn’t dare to defy him.

Said skeleton squats down in front of Killer. Kneeling would be more comfortable, but a god doesn’t kneel.

They’re close now; Nightmare firmly takes the other’s right wrist without breaking eye contact. Right when Killer wants to ask what he was doing, he feels a sharp pain in his forearm.

Did Nightmare just cut him?

He did. One of Nightmare’s tentacles glides over the fresh wound, causing Killer to tremble and hold back a moan.

“Doesn’t life hurt enough on its own? Why do you keep doing this?”, Nightmare asks with honest curiosity, and Killer could swear he saw the other’s smile drop for a fraction of a second.

But Killer is too far gone to care about the hidden meaning of this expression and just answers dazed: “Can you do that again?” They stare at each other intensely for a while.

Until Nightmare inflicts a long cut along his arm, crossing every other of Killer’s cuts in an almost perfectly 90 degree angle.

Killer moans, neither of them knows if it’s because of pain or some wicked pleasure. His free hand quickly grabs Night’s arm and tries to apply more force, cut deeper. But the dark skeleton stops as soon as Killer touches his hand. “Close your eyes.”, he orders, and his puppet obeys without hesitation.

He hears his boss shifting a bit in front of him.

Then, another cut, deeper than the last two. Shorter than the last, but intense, nonetheless. Killer exhales almost relieved. “How does that make you feel?”, Nightmare’s low voice sounds like purring. “…Like somebody just switched off a loudspeaker that was bursting my skull… Like somebody just turned off a blinding light… It’s relieving.”, Killer tries to explain.

Unexpectedly, something warm is dripping on his fresh wounds. Killer frowns and opens his eyes. Foreign marrow is dripping on his wounds. His eyes sockets widen in surprise and the fog of pleasure clears instantly.

Nightmare on the other hand looks unaffected by his own dripping wound. He cut a lot deeper than necessary, due to his underestimation of the sharp blade. Killer knows how to keep a knife sharp. “Boss! Why did you do that?!”, Killer asks shocked, almost offended.

“How does that make you feel?”, Nightmare asks the same question again, completely calm and calculating. The sitting skeleton frowns in concentration. “…Huh? Tibia honest, I feel upset, betrayed and, well, a little helpless right now. Stop the bleeding, boss. I don’t want to see you like this. Was I the reason for you to do this? Don’t do that again, please.”, Killer mutters without thinking much.

Nightmare nods and looks meaningful at his most valuable puppet, waiting for him to think about his own words.

As realization finally hits Killer, he sighs defeated as he gets the message. “Oh, shit… Heh… Sorry.”

“…I need negativity. But that doesn’t mean I want your negativity. That doesn’t mean I get happy when you are depressed. Not really.”, Nightmare states. Killer’s shoulders start trembling. “I know I shouldn’t do this. Sometimes I just can’t help myself, didn’t mean to upset ya, boss.”

Seeing the well-nigh emotionless Killer overwhelmed by different emotions is a rare occurrence. It’ll require some time for his soul to retake the shape of the perfectly round target-symbol. But Nightmare dealt with it before, that shouldn’t be a problem.

“I am aware that this behavior cannot be simply stopped. But no matter how miserable you are feeling, you can talk to me. I will listen, I will understand, and I will take care of you.”, Nightmare sits down beside him again. Killer stares at his arms, now tainted with the marrow of the monster he never wanted to harm.

A tentacle pushes Killer against Night, implying that he allows physical contact. Killer leans against his boss, still having trouble holding back his tears. Nightmare chuckles, “Was that too graphic?”

Killer laughs, a sound that, no matter what caused it, always carries a manic undertone. A cut too graphic? For him? That’s hilarious. “Nah, just unexpected.”, he replies amused.

The tentacle strokes Killer's shoulder soothingly. That’s more like the deadly skeleton he knows.


End file.
